The model below shows a carbide ion. 

What could be done to change this carbide ion to a neutral carbon atom?

remove 2 electrons 

add 2 electrons

remove 4 electrons 

add 4 electrons

Física: un futbolista patea hacia el arco con una velocidad de 15m/ah, calcular: a)el alcance para un ángulo de tiro de 25? , b) el tiempo que el balón permanece en el aire.

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?

Atruck driver is attempting to deliver some furniture. first, he travels 8 km east, and then he turns around and travels 3 km west. finally, he turns again and travels 13 km to his destination. what is the drivers distance